Plz explain me the code

Question

for z in range(int(input())):
a, b, k = map(int, input().split())
x = len(str(a))
p = 10**x
while True:
cur = p-a
cur = (cur+b-1)//b
if cur*x < k:
k -= cur*x
x += 1
p *= 10
a += cur*b
else:
a += b*((k-1)//x)
print(str(a)[(k-1)%x])
break
Bob is writing a program that solves the following problem:
You are given the numbers to display the infinite sequence of numbers . Bob has made a mistake, he namely forgot to draw a space for the division between the numbers, resulting in a long line of numbers. In order not to correct the mistake, Bob decided to find out how to find the digit in the formed line (numbering of digits begins with one).
Bob could not find a good solution, so he asks you for help.
Input format
The first line contains a number denoting the number of tests.
The first line of each test contains four integers .
Output format
Print the digit for each test.

Answer 1

23 i got you